This invention relates to a process for producing powdered food products which contain fats; for example bouillon products, thickeners, soups and sauces. The invention also relates to the powdered food products.
Food products such as bouillon products, thickeners, soups and sauces are usually made up of blends of animal fats, vegetable fats, oils and various powdered ingredients such as salts, spices, flavour enhancers, yeast extracts, and starches. The exact composition varies from flavour to flavour, from application to application, and from manufacturer to manufacturer but the products usually contain in the region of 5 to 25% by weight fat.
Although these products are available in many forms and go through many different states during processing, they are usually not in the form of a flowable powder after the addition of the fats. Special and complicated processing is required to get them into powdered form. However, in many applications, it is convenient to have the products in the form of flowable powders; either during processing or as a final product. For example, consumers would find an instant soup product, which contained a pasty mass, to be unappealing. Similarly for instant thickeners and sauces. It would be very convenient to provide these instant products in powdered form and yet include fats.
Also, for bouillon or stock products, although these are usually sold in the form of solid cubes or tablets, it would be useful during processing to have the product in powdered form. It is conventional to prepare these solid stock products in one of two ways. In the first method, solid fats are melted and mixed. Then the melted fats are cooled on a roller to produce fat flakes made up of crystalline fat. The other ingredients of the stock product are then mixed with the fat flakes and the mixture pressed into stock tablets. The tablets are then wrapped. This is known as the "hard" process. In the second method, the solid fats are melted and then introduced into a jacketed blender where they are mixed with the other ingredients. Thereafter cooling liquid is run through the jacket of the blender to cool the mixture to crystallize the fats. The mixture is then extruded or filled into a preformed wrapping. This is known as the "soft" process.
In the hard process, it is essential for the fats to be at least partially crystallized in order for the mixture of fats and other ingredients to be sufficiently flowable. If the stock product were to be prepared from liquid fat at usual fat levels, it would be in the form of a paste which would not be sufficiently flowable. If the mixtures are not sufficiently flowable. difficulties arise during tabletting; particularly during filling of the presses. Unfortunately, the fats used in stock products are not homogenous making the reliable formation of fat crystals complicated. In particular, temperatures must be carefully controlled in order to obtain the required degree of crystallisation. Also significant amounts of energy are consumed in reducing temperatures to those at which fat crystals form. Similar procedures are required for other flowable food products such as thickeners, soups and sauces.
Also, the maintenance of fat crystals is required for adequate stability of the products. Therefore if it is necessary to store the mixture of crystalline fat and other ingredients, as is often the case, the mixture must be stored at temperatures in the region of about 20.degree. C. or less. Again this results in energy consumption.
Therefore there is a need for a process of producing powdered, fat-containing products which is less complicated and requires less careful control of temperature.